1. Field of the Invention
The present application relates generally to poles, and more particularly to pigging poles for pipelines.
2. Description of Related Art
The term “pigging” as it relates to the pipe industry refers to the process of using inspection gauges and/or cleaning devices, commonly known as pigs, to perform various maintenance operations within a pipe. Referring to FIGS. 1 and 2, a conventional pig 101 and an operably associated pipeline 103 are shown. The pigging process includes inserting pig 101 through a pig launcher 105, commonly known as a launching station, which thereinafter travels through pipe 107 to a pig catcher 109, commonly known also as a receiving station. In some embodiments, a backpressure created within the pipe 107 drives pig 101 between the two stations. Thereafter, pig 101 is manually retrieved from catcher 109 with a pigging pole.
Pig 101 typically includes a cleaning section 111 for cleaning the inner surfaces of pipe 107 and is preferably disposed between and rigidly attached to a front section 113 and a rear section 115. Front section 113 includes a loop 117 or other suitable means for removing pig 101 from catcher 109. The rear section 115 includes a relatively flat surface 119 for pushing thereagainst during the process of inserting pig 101 into pipe 107.
In alternative embodiments, pig 101 is devoid of a loop 117 or it is possible that loop 117 is damaged due to the high forces exerted thereagainst during the removal process. Pig 101 is further provided with a pliable lip 119 and an associated back surface 121. During use, pig 101 fits snugly within pipe 107 such that lip 119 comes into contact with the inner surface (not shown) of pipe 107.
FIG. 3 depicts a conventional pigging pole 301 used to insert and retrieve pig 101. Pole 301 comprises of a shaft 303 that rigidly attaches to a ram 305. During use, a worker lifts and manipulates pole 301 to push pig 101 within pipe 107. Thereafter, a hook 307 rigidly attached to pole 301 is used to retrieve pig 101 via loop 117.
Pole 301 has been shown to be an effective means for inserting and retrieving pig 101; however, considerable shortcomings remain. For example, shaft 303 is a single pole having sufficient length for extending the reach within both launcher 105 and catcher 109 to insert and retrieve pig 101, respectively, which in turn does not facilitate easy transporting of pole 301 between multiple pipelines. Thus, presently a pigging pole is left at each pipeline for use.
Another disadvantage includes the arduous task of retrieving pig 101 from within catcher 109. It should be understood that catcher 109 is enclosed area that restricts entering light and viewing access of hook 307 relative to loop 115, resulting in excessive time and effort exhausted in retrieving pig 101. In most scenarios, the worker is forced to guess the positioning of hook 307 relative to loop 117.
In addition, it has been shown that excessive force is required to remove the tightly fitted pig 101 from within pipe 107, resulting in large forces exerted thereagainst, which in turn can damage loop 117. It is a long-felt need to retrieve pig 101 when pig 101 is devoid of or has a damaged loop 115.
Although the foregoing developments represent great strides in the area of pigging poles, many shortcomings remain.
While the pigging pole and method of use is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the process of the present application as defined by the appended claims.